Private Sub FillCollection()
      Dim hashtable1 As New Hashtable(256)
      Dim control1 As Control
      For Each control1 In MyBase.Controls
            If TypeOf control1 Is Button Then
                  hashtable1.Add(control1.Name, control1)
            End If
      Next
End Sub

Dim button1 As Button = CType(hashtable1.Item("b2"), Button)
button1.Enabled = False